Michelle Tyler told a news conference that she met with Filner on June 11 to ask for his help with Veterans Affairs department on behalf of Katherine Ragazzino, who was injured in Iraq and spent 18 months in the hospital as a result.
Ten other women have made similar allegations against Filner, claiming inappropriate advances and contact. Filner has vowed to enter into behavioral therapy.
His office did not immediately respond to requests for comment.
Tyler said she first met with Filner on the same issue in 2011, when he was a congressman, and reached out again in June.
Tyler was in a meeting with Filner and Ragazzino and a VA representative when he requested to be alone with her before repeatedly asking for a date, she said.
Filner "made it very clear to me that his expectation was that his help for Katherine depended on my willingness to go to dinner with him, spend personal time with him and be seen in public with him," said Tyler, flanked by women's rights attorney Gloria Allred.
Tyler is the caregiver for Ragazzino, who suffers from a traumatic brain injury and post-traumatic stress disorder.
Ragazzino said she had struggled with the VA for help, and was homeless and living out of her car when she met Tyler. Ragazzino said there are still unresolved issues with the VA, but she didn't specify.